What do you do in a betting round?

If you don't want to continue in the hand, you can throw your cards away and "leave" the current round.

Bet

When no-one before you has bet anything, you can do so yourself. You would say, for example: "I bet 10 chips" and place your chips in the pot, so that anyone who wants to continue playing must match your bet. If they don't, because it is too expensive or they don’t have a good hand, they can fold.

Betting all of one's chips is called going all-in. Once you are all-in, you can't bet anything more, but also cannot be forced to fold anymore. Indeed, when you are all-in, you will automatically be in the hand until its end, giving you the possibility to win by showing the best cards. Raise

You can also raise a bet; for example, raise an opponent's bet of 10 chips to 20 chips. By doing this you are making the bet more expensive to call for anyone who wants to play on. If they don't want to pay extra, they have to fold. Call

If someone before you has bet, you have the possibility to call this bet. For this you just pay whatever the price of the bet was. If an opponent bets 10 chips, you would have to call 10 chips to stay in the hand. Check

If no-one has bet yet, then you can check. This means that you don't place any bets and let the next player act. It is like saying "I'll wait and see what happens".